A mobile telecommunication system, as illustrated schematically in FIG. 1, generally comprises a plurality of user-devices. In a Universal Mobile Telecommunication System (UMTS) such user-devices are referred to as the User Equipment (UE). A UMTS User Equipment (UE) consists of the terminal, referred to as the Mobile Equipment (ME), and a smart card referred to as the User Subscriber Identity Module (USIM). The USIM provides a user with access to subscribed services irrespective of the specific Mobile Equipment (ME) used. Hence, by inserting a USIM-card into a Mobile Equipment (ME), the user is able to receive calls at that equipment, make calls from that equipment, and receive other subscribed services. Almost every telecommunication system comprises user-devices of some kind. For example, a user-device in the Global System for Mobile Communications (GSM) is referred to as the Mobile Station (MS), which essentially corresponds to the User Equipment (UE) in the UMTS-system.
A mobile telecommunication system also generally comprises a telecommunication network for connecting a user-device to a service provided through the network and/or by the network. A user-device in a mobile telecommunication system is typically connected to the telecommunication network via a radio access point. Access points in the UMTS-system are referred to as Node B. A Node B houses one or several radio transceivers and handles the radio-link protocols with the User Equipment (UE). Each Node B provides radio coverage in a specific area and therefore effectively defines the cell of the UMTS cellular system. In a large urban area, there will potentially be a large number of Node B(s) deployed. The corresponding access points in a GSM-system are referred to as Base Transceiver Stations (BTS). Other telecommunication systems may have other kind of radio access points or radio nodes for connecting a user-device to a telecommunication network.
One or several access points in a general telecommunication network may in turn be connected to a controller. In an UMTS-system such controllers are referred to as a Radio Network Controller (RNC). The RNC is responsible for the control of a group of Node B(s), where it monitors each call and i.a. decides when to handover the call from one Node B to another. The RNC also commands exchange functions and control of the radio frequency power levels of the associated group of Node B(s). Corresponding controllers in a GSM system is referred to as Base Station Controller (BSC). Other telecommunication systems may have other types of controllers or nodes for managing a group of access points.
One or several access point controllers in a general telecommunication network may in turn be connected to a switching centre or similar. A switching centre may be referred to as a Mobile-services Switching Centre (MSC), which is the common expression in both UMTS and GSM. The MSC is a complete exchange, capable of routing calls from a fixed network via the BSC/RNC and BTS/Node B to an individual MS/UE. The fixed network may e.g. be a Public Switched Telephone Network (PSTN), a Circuit Switched Public Data Network (CSPDN) or a Packet Switched Public Data Network (PSPDN) or similar. The MSC also serves to co-ordinate setting up calls to and from UMTS/GSM users, i.e. between individual UE(s)/MS(s). The MSC has e.g. a correspondence in the Serving GPRS Support Node (SGSN) in a General Packet Radio Service system (GPRS).
In UMTS, a RNC and its underlying Node B(s) are referred to as a Radio Network Subsystem (RNS), whereas in GSM a BSC and its underlying BTS(s) is referred to as a Base Station Subsystem (BSS). In order to obtain radio coverage of a given geographical area, a number of RNS(s)/BSS(s) are normally required; i.e. each MSC would thus have to interface to one or more RNS(s)/BSS(s). In addition more than one MSC(s) may be required to cover a country. The MSC and associated components may in turn be denoted the Network Subsystem (NSS) or the Core Network (CN).
The communication between the different parts in an UMTS-system and/or a GSM-system, are conducted via standardised interfaces allowing operation between components made by different suppliers. An UMTS User Equipment (UE) communicates with a Node B via an Uu-interface, whereas a Node B communicates with a Radio Network Controller (RNC) via an Iub-interface. In turn, the RNC communicates with a Mobile-service Switching Centre (MSC) via an Iu-interface. A GSM Mobile Station (MS) communicates with a Base Transceiver Station (BTS) via an Um-interface, whereas a BTS communicates with a Base Station Controller (BSC) via an Abis-interface. In turn, the BSC communicates with a Mobile-service Switching Centre (MSC) via an A-interface.
Such mobile or wireless telecommunication systems as the GSM and the UMTS described above are generally organised in a hierarchic structure. However, a mobile or wireless telecommunication system can have vast variety of different structures, e.g. depending on the underlying technique, the performance needed, the acceptable economic costs etc. Other mobile or wireless telecommunication systems may e.g. be structured as a ring network or a bus network or as a star network etc.
The mobile telecommunication systems as indicated above may have different quality of service supplied to different users of the system. One such differentiation of the quality of service can be accomplished by dividing the users of a particular telecommunication system into groups, where the users in a specific group may be provided with a certain quality of service, which may differ from one group to another. The specific quality of service that is supplied to a certain group of users may be determined by assigning a priority level to each group. A higher priority may result in a higher quality of service and a lower priority may result in a lower quality of service.
Many mobile telecommunication systems support such a group priority. However, the priority level for a user is normally fixed and kept the same in all areas covered by the system. Some mobile telecommunication systems also support a type of access differentiation that provides some users with exclusive access to certain parts of the system. For example, a certain base station in a GSM-system may only be accessed by a small group of users, whereas other users of the same system are prohibited from accessing this particular base station. However, a possible priority level for a user with access to a particular base station is normally fixed and the quality of service corresponds either to access or to no access.
Accordingly, in known mobile telecommunication systems a user may be assigned a certain priority level and a certain quality of service within a certain coverage area of a mobile telecommunication system. However, the priority levels and the quality of service are coarsely segmented and essentially static. Accordingly, there is a need for an improved distribution of the quality of service within a telecommunication system.